The 31-year-old Wade, who hit a career-high .260 last season and has contributed many timely hits during his four-plus seasons with the Giants, was batting .167 (24 for 144) in 50 games this year.

Posey made a series of bold roster changes Wednesday morning in an effort to jolt the Giants' slumbering offense.

San Francisco also designated backup catcher Sam Huff for assignment and optioned infielder Christian Koss to Triple-A Sacramento. To fill their three roster spots, the team signed veteran first baseman Dominic Smith to a major-league contract and selected outfielder Daniel Johnson and catcher Andrew Knizner from Sacramento.